The statistical distribution of the individual wave heights and periods in an ocean wave record and their joint distribution are investigated. Theoretical distribution functions based on a narrow band spectrum are compared with recorded wave data. Ocean waves recorded during the September 1961 storm in the North Atlantic are used for this purpose. The data are found to correlate reasonably well with the theoretical distribution curves.

Statistical distributions of the sea surface wave heights and periods have drawn considerable attention in the past. In a recent paper, Longuet-Higgins <1975> discussed a theoretical result on the joint distribution of individual wave heights and periods in a record (Figure 1). The assumption of a narrow band spectrum was made in the analysis.

The purpose of this note is to compare these theoretical distributions of Longuet-Higgins <1952, 1958, 1962, 1975> with wave data recorded during a storm in 1961 in the North Atlantic. In general, the energy density spectra computed from these records do not fall in the category of narrow band spectra. Thus the applicability of the theoretical formulas for narrow band spectra on individual wave height and period distributions and on the joint distribution of the heights and periods from wave records with wide band spectra is tested.

In September 1961, high seas were encountered by the O.W.S. Weather Reporter underway from the United Kingdom to station J (near 53 ¿N, 18 ¿W). The water surface elevations were recorded by the shipborne wave recorder during this storm. Wave data taken at 3-hour intervals from 0000 UT on September 12 to 2100 UT on September 15 are used in the present analysis. The lengths of the records were between 11 and 14 min.